Apparatus, program, medium for image-area separation, image processing and image forming

ABSTRACT

An image-area separation apparatus includes a SIMD processor performing a SIMD process for performing an image-area separation process and an image-area separation mechanism for performing an image-separation operation according to the SIMD process performed by the SIMD processor. The image-area separating apparatus performs an image-area separation operation to separate character images from figure images by means of software while the SIMD-typed processor achieves a high-speed image data processing.

[0001] This application is related to Japanese patent application, No.JPAP2002-208209, filed on Jul. 17, 2002 in the Japanese Patent Office,the entire contents of which are incorporated by reference herein.

FIELD OF INVENTION

[0002] The present invention relates to an image-area separationapparatus, an image processing apparatus, and an image formingapparatus. The present invention also relates to a program and a mediumfor image-area separation, image processing, and image forming.

BACKGROUND OF THE INVENTION

[0003] Recently, an image processing apparatus to perform an imageprocessing of digital image data has been applied in copying machines,facsimiles, printers, scanners and so forth. In the above-describedimage processing apparatuses, image data are required to be processedmore rapidly and for this purpose, the apparatuses have in recent yearsstarted to include hardware such as an Application Specified IntegratedCircuit (ASIC).

[0004] When image data containing both a portion represented in dotssuch as pictures or photographs, for example, and another portionrepresented in line such as characters, for example, are output to aprint medium, some measures need to be taken to eliminate moiré, forexample for pictures and pattern portion so as to refine image qualityand also some other measures need to be taken for characters, such as aclarification process, for example.

[0005] In order to automatically perform the above-described processesin compliance with respective image data, an image-area separationtechnology is known to automatically image-separate picture and patternportions, respectively. Published Japanese Patent Application Laid-OpenPublication No. 2777378 discloses the above-described image processingapparatus.

[0006] It is also well known that although different figures anddifferent characters of image data have different attributes accordingto different pixels, respectively. The attributes of the pixels that arealigned adjacent tend to influence to each other to become nearlyidentical images. It is desired that the discrimination resultassociated with attributes be an area that has a dimension large enoughto some extent so that the discrimination result allows the image datato be easily determined. Published Japanese Patent Laid-Open PublicationNo. 3256267 describes a technology in which to accurately obtain thecharacter area from surrounding pixels when a pixel has been determinedas a character, the pixels surrounding a pixel of interest is alsoeasily determined as a character in accordance with the weight orprobability with respect to the distance between the pixel which hasbeen determined as a character and a specified pixel.

[0007] However, in conventional image processing apparatuses, aplurality of circuits may be pre-mounted or an ASIC may be exchangedwhen the contents of image processing data are required to be replaced,thus making it difficult to change the contents of the image processingapparatus with flexibility. It may also be considered an alternative toperform an image processing by changing software configuration usinggeneral-purpose microprocessors. However, this method has also a defectin that it takes a large amount of time to process data.

SUMMARY OF THE INVENTION

[0008] In view of the foregoing, it is an object of the presentinvention to provide a novel image-separating apparatus for performingan image-area separation operation to separate character images fromfigure images by means of software while a SIMD-(single instructionmultiple data stream) typed processor achieves a high-speed image dataprocessing.

[0009] Another object of the present invention is to provide a novelcomputer-readable program which performs an image-area separationoperation to separate character images from figure images by means ofsoftware while the SIMD-typed processor achieves a high-speed image dataprocessing.

[0010] Another object of the present invention is to provide a novelcomputer-readable media having stored thereon computer-executableinstructions which perform an image-area separation operation toseparate character images from figure images by means of software whilethe SIMD-typed processor achieves a high-speed image data processing.

[0011] A novel image-area separation apparatus in accordance with theinvention includes a SIMD processor performing a SIMD process forperforming an image-area separation process and image-area separationmechanism for performing an image-separation operation according to theSIMD process performed by the SIMD processor. The image-separationmechanism image-separates the image data into a character portion and afigure portion. The image-area separation apparatus further includes aplurality of characteristic test mechanisms for performing a pluralityof characteristic tests to determine whether the image data havespecific characteristics and a comprehensive test mechanism fordetermining a comprehensive test result according to the plurality ofthe characteristic tests mechanisms performed by the plurality of testmechanisms.

[0012] The characteristics test mechanisms include a characteristic testmechanism to determine whether the image data includes edge data; acharacteristic test mechanism to determine whether the image dataincludes dotted image data, and a characteristic test mechanism todetermine whether the image data includes line screen image data.

[0013] The comprehensive test mechanism is used to determine whether theimage data includes a character portion, and whether the image dataincludes a figure portion. More specifically, the comprehensive testmechanism determines that the image data includes a character portionwhen the edge test mechanism determines the image data include at leastone edge component, the dotted image test mechanism determines that theimage data include no dotted image component, and the line screen testmechanism determines that the image data include no line screen. Thecomprehensive test mechanism determines that the image data include afigure portion when at least one of three events occurs in which: theedge test mechanism determines that the image data include no edgecomponent; the dotted image test mechanism determines that the imagedata include one of at least dotted components; or the line screen testmechanism determines that the image data include at least one of linescreen components.

[0014] In the image-area separation apparatus, the SIMD processorincludes a register storing data forming a register file. The image-areaseparation apparatus further includes a data converter for convertingdata using the data as an address stored in the register wherein theimage-area separation mechanism includes a data table converterconnected to the SIMD processor for converting data of a data tableusing, as an address, data of a register provided to the SIMD processor,and performs the image-area separation operation by causing the SIMDprocessor to perform the SIMD process and the data table converter toperform a sequential operation. In the image-area separation apparatus,the image-area separation mechanism requests intermediate data in theSIMD process and performs the sequential operation for the intermediatedata.

[0015] Further to achieve these and other objects, in one embodiment, anovel image-processing mechanism is provided for switching over contentsof the image data in accordance with the result of the image-separationoperation performed by the image-separation apparatus. The image formingapparatus includes an image reading apparatus to read an image of anoriginal image data, an image-area separation apparatus which processesthe read image of the original image data and the image-processingmechanism for switching over contents of the image data in accordancewith the result of the image-separation operation performed by theimage-separation apparatus and an image forming mechanism for forming animage onto a recording sheet in accordance with the image data read bythe image reading apparatus.

[0016] Further, to achieve these and other objects, a novelcomputer-readable program for an image-area separation embodied on aninformation storage medium including processing routines executed by aSIMD processor includes the step of causing the SIMD processor toperform the image-area separation for image-separating the image data.

[0017] The image-area separation operation image-separates the imagedata into a character portion and a figure portion. Thecomputer-readable program for the image-area separation also includes aplurality of characteristic test mechanisms for performing a pluralityof characteristic tests to determine whether the image data havespecific characteristics, and a comprehensive test mechanism fordetermining a comprehensive test result according to the plurality ofthe characteristic test mechanisms performed by the plurality of testmechanisms. In the computer-readable program, one of a plurality of thecharacteristic test processes is an edge test process to determine thatthe image data includes an edge component, a dot image test process todetermine that the image data includes a dotted image component and aline screen test process to determine that the image data includes aline screen component. In the computer-readable program, the image-areaseparation process causes the SIMD-typed processor to execute the SIMDprocess and to perform the image-area separation by allowing a tableconverter which performs a table conversion in which register data ofthe register file of the SIMD-typed processor are an address to executea sequential process. In the computer-readable program, the image-areaseparation calculates intermediate data and performs the sequentialprocess in accordance with the intermediate data.

[0018] To achieve the above-mentioned object, a novel computer-readablemedium having stored thereon computer-executable instructions whichinclude the step of causing the SIMD processor to perform the image-areaseparation for image-separating the image data. In the computer-readablemedium for the image-area separation, the image-area separationoperation image-separates the image data into a character portion and afigure portion. The computer-readable medium for the image-areaseparation includes a plurality of characteristic test mechanisms forperforming a plurality of characteristic tests to determine whether theimage data have specific characteristics, and a comprehensive testmechanism for determining a comprehensive test result according to theplurality of the characteristic test mechanisms performed by theplurality of test mechanisms. One of the characteristic test processesis an edge test process to determine that the image data include an edgecomponent. Another characteristic test processes is a dot image testprocess to determine that the image data include a dotted imagecomponent. Another characteristic test processes is a line screen testprocess to determine that the image data include a line screencomponents. In the computer-readable medium, the image-area separationprocess causes the SIMD-typed processor to execute the SIMD process andto perform the image-area separation by allowing a table converter whichperforms a table conversion in which register data of the register fileof the SIMD-typed processor are an address to execute a sequentialprocess. In the computer-readable medium, the image-area separationcalculates intermediate data and performs the sequential process inaccordance with the intermediate data.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] A more complete appreciation of the disclosure and many of theattendant advantages thereof will be readily obtained as the samebecomes better understood by reference to the following detaileddescription when considered in connection with the accompanyingdrawings, wherein:

[0020]FIG. 1 is a block diagram showing an exemplary structure of thedigital color copying machine according to a preferred embodiment of thepresent invention;

[0021]FIG. 2 is a block diagram showing an exemplary function of animage-area separation apparatus of the digital color copying machine;

[0022]FIG. 3 is a block diagram showing an exemplary structure of aSIMD-typed processor of the image-area separation apparatus;

[0023]FIG. 4 is a block diagram showing an exemplary structure of theSIMD-typed processor;

[0024]FIG. 5 is an illustration showing an exemplary process of an edgedetermination;

[0025]FIG. 6 is an illustration showing an exemplary process of a dottedimage determination;

[0026]FIG. 7 is an illustration showing an exemplary process of thedotted image determination;

[0027]FIG. 8 is a block diagram showing an exemplary structure of a linescreen determination method;

[0028]FIG. 9 is a block diagram showing an exemplary structure of avertical line screen determination unit;

[0029]FIG. 10 is an illustration showing an exemplary process of a linescreen determination;

[0030]FIG. 11 is an illustration showing an exemplary process of theline screen determination method;

[0031]FIG. 12 is an illustration showing an exemplary process todetermine precisely a dotted image included in the line screen toprevent a dotted image area from extremely expanding and from reachingto an image area that is not a dotted image;

[0032]FIG. 13 is a block diagram showing an exemplary hardwarecomposition of the image-area separation apparatus;

[0033]FIG. 14 is an illustration showing detailed processes of FIG. 12;

[0034]FIG. 15 is a block diagram showing a detailed structure of theSIMD-typed processor of FIG. 3 and also a block diagram of a tableconverter according to the preferred embodiment of the presentinvention;

[0035]FIG. 16 is an illustration showing a status associated with atable conversion using the table converter;

[0036]FIG. 17 is a state transition diagram showing a status associatedwith the table conversion using the table converter; and

[0037]FIG. 18 is an illustration showing a table used in the tableconverter.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0038] In describing preferred embodiments illustrated in the drawings,specific terminology is employed for the sake of clarity. However, thedisclosure of this patent specification is not intended to be limited tothe specific terminology so selected and it is to be understood thateach specific element includes all technical equivalents that operate ina similar manner. Referring now to the drawings, wherein like referencenumerals designate identical or corresponding parts throughout theseveral views, particularly to FIG. 1, a description is made for amulti-function machine 1 according to a preferred embodiment of thepresent invention. FIG. 1 is a block diagram of a multi-function machine1 (hereinafter referred to as a copying machine 1). As illustrated inFIG. 1, the copying machine 1, an apparatus which embodies an imageforming apparatus, includes a scanner 2, a printer 3, a control panel 4,a system controller 5, a synchronous control circuit 11, a backgrounddetection circuit 12, an image-area separation apparatus 13, an imageprocessing unit 14, an Automatic Color Selection (ACS) 15. The imageprocessing unit 14 of the copying machine 1 includes a scanner gammacircuit 21, a smoothing filter 22, a background elimination circuit 23,a color compensation circuit 24, an edge filter emphasis circuit 25, aprinter gamma circuit 26, a gradation processing circuit 27 and aselector 28.

[0039] As shown in FIG. 1, the scanner 2 scans the entire originalsurface of an image and performs a digital signal processing of the readimage. The printer 3 forms a color or a mono chrome image onto arecording sheet using color toner including magenta (M), cyan (C),yellow (Y) and black (Bk) using an electrographic method correspondingto the original image read by the scanner 2. The control panel 4 isoperable with manipulation by a user and the system controller 5 whichincludes microcomputers controls the respective components of thecopying machine 1. The synchronous control circuit 11 generates andsupplies pulse signals to various circuits 21-27, which accept inputdata in synchronism with the pulse signals. The synchronous controlcircuit 11 also supplies pulse signals to the background detectioncircuit 12, which is used to detect the white background level of anoriginal image that is read by the scanner 2.

[0040] The image-area separation apparatus 13 image-separates a figureportion from a character portion of the original image and the imageprocessing unit 14 and the ACS 15 processes image data read by thescanner 2 to achieve an image processing operation and an image-areaseparation operation. The image processing unit 14 performs the imageprocessing operation. The image processing unit 14 and the image-areaseparation apparatus 13 are used to perform the image-area separationoperation. The scanner gamma circuit 21 which resides in the imageprocessing unit 14 of the copying machine 1 converts raw imagecomponents read by the scanner to linear R, G, B image data. Thesmoothing filter 22 performs a smoothing process in the image-areaseparation operation and the image processing operation. The backgroundelimination circuit 23 eliminates the white background of an originalimage.

[0041] The color compensation circuit 24 compensates the color image inthe image processing operation. The edge emphasis filter circuit 25performs an edge emphasis process and the printer gamma circuit 26converts image data into a density linear after setting a curve inaccordance with the characteristic of the printer 3. The gradationprocessing circuit 27 performs a gradation processing of image data tohave a predetermined bit width (8 bits). The gradation processingcircuit 27 and the selector 28 then outputs the processed image data tothe printer 3. The color compensation circuit 24 converts the image datacomponents of R, G and B into an image data components of Y, M and C,extracts the black color elements included in the composite part of theimage data Y, M and C, forms the image data for the Bk out of Y, M and Ccolor components by eliminating the black color elements and creates animage data containing the Y, M and C color elements. The selector 28sequentially selects the respective electric signal containing colorinformation from image data and outputs the selected signal containingthe color information to the edge emphasis filter circuit 25.

[0042] Referring now to the image-area separation apparatus 13 of FIG.2, a flowchart illustrating an exemplary process executed by a SIMD (asingle instruction-stream multiple data-stream)-typed processor 41 aswill be described later is shown. As illustrated in FIG. 2, theprocesses to be executed by the SIMD-typed processor includes a testprocess to determine whether or not specified image data contain an edgearea portion in Step S1, a dotted test process to determine whether ornot image data contain dots in Step S2 and a line screen test process todetermine whether or not specified image data contain a line screen inStep S3. Based on each of the above-described Steps from S1 through S3,a Step S4 (not shown) is a process to determine whether image data areincluded in a character portion or a figure portion. After determiningwhether image data correspond to figures or characters, a comprehensivetest process is executed in which test signals created based upon theabove-described process of the test process are output to the imageprocessing unit 14. Hence, the image-area separation process isperformed to determine existence of a characteristic of image dataaccording to each of the functions performed in the above-describedprocesses.

[0043] Referring now to FIG. 13, a block diagram shows a hardwarestructure of the image-area separation apparatus 13. As illustrated inFIG. 13, the image-area separation apparatus includes the SIMD-typedprocessor 41, a read-only memory (ROM) 45, a random-access memory (RAM)46, an I/O port 44 (not shown), an I/O port 47 and an internal bus 48.

[0044] The SIMD-typed processor 41 performs various operationsassociated with the image-separation operation and makes a uniformcontrol on each part of the image-area separation apparatus 13. The ROM45 functions as a medium in the preferred embodiment of the presentinvention and stores various readable control programs and fixed datafor the image-separation operation and the image processing operation.The RAM 46 stores various data which are rewritable and serves as a workarea of the SIMD-typed processor 41. The RAM 46 is connected with theI/O port 47 through the internal bus 48. The ROM 45 allows the controlprograms for the image-separation operation which are stored in a flashmemory to be downloaded and to be rewritten from an external equipment(not shown) through the I/O port 44.

[0045] Referring to FIGS. 3 and 4, the SIMD-typed processor 41 includesa global processor (hereinafter referred to as the GP) 42, a registerfile 43 and an operation array 44. The GP 42 includes a program RAM (notshown) and a data RAM (not shown) for the image-separation operation andreads the control program for the image-separation operation and theimage processing operation that are mounted in the ROM 45 and generatesvarious types of image control signals through an image forming medium.The image signals are not only utilized for controlling various imagedata blocks included in the ROM 45 (FIG. 13) but are supplied to theregister file 43 and the operation array 44. When the GP 42 executes aninstruction, various kinds of operations and program control operationsto perform the image-separation operation and image processing operationare performed with the use of a general-purpose register 53 and anarithmetic logic unit (ALU) (not shown) mounted in the SIMD-typedprocessor 41 as will be explained later.

[0046] The register file 43 stores print data processed by aninstruction of a processor element (hereinafter referred to as the PE).The instruction of the PE is SIMD-typed and performs a uniform processsimultaneously for a plurality of print data stored in the register file43. The PE instructs to read specified print data from the register file43 and it is from an instruction of the GP 42 that the PE controls toread and write the specified print data. The print data read from theregister file 43 are transferred to the operation array 44. The printdata transferred are processed in the operation array 44 and are writteninto the register file 43.

[0047] The operation array 44 performs the process for theimage-separation operation in accordance with an instruction of the PE.The processes and controls associated with the image-area separationoperation and the image processing operation are performed by the GP 42.

[0048] Referring now to FIG. 4, the SIMD-typed processor 41 which is aone-dimension arranged SIMD-typed processor executes a singleinstruction with a high degree of parallelism for one or more printdata. As shown in FIG. 4, the register file 43 includes one-dimensionarranged processor element (PE) array 52 including a plurality of thePEs 51.

[0049] The GP 42 includes a program counter (PC) (not shown) whichstores each of the program addresses, a general-purpose register (notshown) for storing operation data used for the image-separationoperation, a stack pointer (SP) (not shown) to store each of the RAMaddresses of the area in which the print data are saved at the time ofdata register save and restore, a link register (LS)(not shown) to storethe originating address when calling the subroutine, an LI register (notshown) and an LN register (not shown) to store the branch point addressof data at the time of interrupt request and non-maskable interrupt anda processor state register (not shown) to store a state of theSIMD-typed processor 41.

[0050] The GP 42 executes an instruction of the GP with the use of aninstruction decoder (not shown), an arithmetic logic unit (ALU) (notshown), a memory control circuit (not shown), an interrupt controlcircuit (not shown), an external I/O control circuit (not shown) and aGP arithmetic control circuit (not shown). The GP 42 also controls theregister file 43 and the operation array 44 when executing a PEinstruction 43 with the use of the instruction decoder (not shown), aregister file control circuit (not shown) and a PE arithmetic controlcircuit (not shown).

[0051] The register file 43 includes one-dimension arranged PE array 52including 256 PEs 51. Each of the PEs 51 includes thirty-two registers53 each with a predetermined bit width of 8 bits. Each register 53 iscalled from R0, through R31 by every unit of the PE 51. The register 53has one reading port and one writing port to be interconnected to theoperation array 44 and may be accessed from the operation array 44through a bus with 8 bits which is readable and rewritable. Twenty-fourout of the thirty-two registers 53 which correspond to the registers R0through R23, respectively, are allowed to be accessed from an externalequipment and with an input from an external equipment clock, an addressand read/write control for the image-separation operation, specifiedimage data may be read and written onto the specified register 53.Although the remaining eight registers which correspond to the registersR24, respectively, through R31, are used for temporarily storing processdata for the PE arithmetic, the image data stored in the RAM of the GP42 may be written therein. The data stored in the RAM of the GP 42 maybe written into one or more of the PEs 51 which satisfy a condition thatis specified by the write control by the GP 42 and a condition of acondition register 58 or T register 59. Because the data RAM has anoutput port of 64 bits width, image data may be written simultaneouslyin eight registers R24 through R 31 for one PE 51, allowing a total of64-bit data to be written.

[0052] The operation array 44 includes the 16-bit ALU 55, a 16-bit Aregister 56, an F register 57 and a condition selector 59. The processis performed by the PE in such a manner that the image data read fromthe register file 43 or the data transferred by the GP 42 are input to ahalf part of the ALU 55 on one hand and that on the other hand theinformation contents of the A register 56 are input to the other half ofthe ALU 55 and the arithmetic results are stored in the A register 56.Thus, an arithmetic operation is performed between the A register 56 andthe registers 53 of R0 through R31 or between the A register 56 and thedata given by the GP 42. The data of the 8-bit register file 43 areinput to the ALU 55 by a shift and expansion circuit (not shown) mountedon the connection part with the operation array 44 with arbitrary bitshifted to left.

[0053] The registers 53 are sequentially connected one to anotherthrough an address bus or a data bus (not shown) where instruction codesto specify operations and the target data to be processed are stored.The information contents of the register 53 are input to the ALU 55 andthe process results are stored in the A register 56. To retrieve dataresult produced in the process of the image-area operation and the imageprocessing operation to an external equipment from the PE 51, the dataare temporarily saved in the F register 57. By retrieving the contentsof the F register 57 the result data after the execution of the dataprocess for the target data may be attained. The instruction code isgiven as uniform contents but in a different status for every PE 51 andeach of the PEs 51 refers to the contents of the data stored in theregister 53 of another adjacent PE 51 in the multiplexer 54. Theoperation results are further processed in a parallel processing and areinput to each of the A registers 56.

[0054] Referring back to FIG. 13, in accordance with the control programfor the image-separation operation and the image processing operationwhich is stored in the ROM 45, the SIMD-typed processor 41 operates inthe RAM 46 as a work area and by so doing each of the processes of theSteps S1 through S4 described above is performed.

[0055] Detailed contents of the necessary process will be explainedbelow.

[0056] Referring to FIG. 5, the edge test process in Step S1 todetermine whether or not specified image data have edge components isexplained. Assuming that a pixel value of a pixel of interest as f11, itmay be determined whether the pixel of interest in units of pixelcomponents is an edge component by a bias between one pixel value and agroup of three pixels by three surrounding pixels. More specifically,the pixel of interest, in other words, the pixel of interest f11 isdetermined to be an edge component when one of the followinginequalities is satisfied. |f11−f00|> thredge, |f11−f00−> thredge,|f11−f02|> thredge, |f11−f10|> thredge, |f11−f12|> thredge, |f11−f20 |>thredge, |f11−f21|> thredge and |f11−f22|>, wherein the symbol thredge“||” is a calculation formula that gives an absolute value and thredge isa pre-determined threshold.

[0057] The dotted image test process in Step S2 to determine whether ornot image data contain dot components is explained.

[0058] Referring to FIGS. 6 and 7, assuming that a pixel value of thepixel of interest is given as f22, it is determined whether the pixel ofinterest is a dotted image with the use of a bias of a pixel value fromsurrounding five pixels x five pixels. More specifically, assuming thefollowing conditions are given:t1=|f22*2−(fD2+f42)|,t2=|f22*2−(f20+f24)|, t3=|f22*2−(f00+f44)| and t4=|f22*2−(f04+f40)|,

[0059] and when the following inequalities are satisfied:

t1>thredge, t2>thredge, t3>thredge and t4>thredge.

[0060] The pixel f22 of interest is determined as a dotted image. It isnoted that the symbol “| |” is a calculation formula as is same withdescribed above, to calculate an absolute value and thredge is apre-assigned threshold.

[0061] The line screen test process in Step S3 (FIG. 2) to determinewhether or not image data have a line screen is explained.

[0062] Referring to FIG. 8, a flowchart shows an exemplary processperformed in Step S3 by the line screen test process. As shown in FIG.8, the exemplary process performed in Step S3 in the line screen testprocess includes a vertical line screen process to detect a line screencomposed of a plurality of lines which spread from one point to theother point along in the sub-scanning direction in Step S11, ahorizontal line screen process to detect a line screen composed of aplurality of lines which spread from one point to the other point alongin the main-scanning direction in Step S12 and the comprehensive testprocess to detect existence of a line screen in Step S13 with referenceto both of the test result of the vertical line screen process and thehorizontal line screen process.

[0063] Referring to FIG. 9, a block diagram shows a process of thevertical line screen process in Step S11. As shown in FIG. 9, thevertical line screen process in Step S11 performs an addition processing65 to add a pixel value amounting to five pixels arranged in a unit ofrow to each one of five data streams of image data 64, which is a unitof the image data handled by the vertical line screen process and whichincludes a total of five pixels widthwise and five pixels latitudinally.Eight patterns of addition/comparison processes 66 and two patterns ofaddition/comparison processes 67 are performed for five addition valuesfrom P1 through P5. In other words, the calculation allows forsubtraction between an addition value and another adjacent additionvalue among the addition values P1 through P5 and the subtractionresults and predetermined values th1 and th2 are compared with thepredetermined th1 and th2 and two types of logical AND test processes 68a and 68 b are performed for the above-described results. In each ANDtest processes 68 a and 68 b, logical AND between the four types ofsubtraction/comparison processes 66 and one type of thesubtraction/comparison process 67 is carried out and the result oflogical AND is obtained and a logical OR is also obtained through the ORtest process.

[0064] Referring to FIGS. 10A, 10B, 10C and 10D, a series of processesperformed in Step S3 in the line screen test process are explained.FIGS. 10A, 10B, 10C and 10D show the relation between a position of animage in the horizontal line and the density in the vertical line. Anideal pattern of image of lines in characters is FIG. 10A. However, inan actual image such as characters, for example, the edge portion may beblurred as shown in FIG. 10B. Because the figure portion whose gradationis represented in line screen image includes a plurality of lines, thesame applies to the above-described characters and an ideal image is theimage as shown in FIG. 10A. However, as is the case with characterportion, the edge portion is also smoothed as shown in FIGS. 10C and10D. The figure shown in FIG. 10C is a relatively thin image portion andthe figure of 10D is a relatively thick image portion. The images inFIGS. 10A, 10B, 10C and 10D are formed in an electro-photographictechnology so that a certain level of density exists in the whitebackground level portion because toner scatters on the background levelwhich correspond an area between the black density levels. Hence, thebias of the density levels between a black figure portion and the whitebackground portion becomes smaller in FIGS. 10C and 10D due to the biasof the density levels between black line in character portion and thewhite background of FIG. 10B.

[0065] Referring to FIG. 12, a test pattern process to determine thefigure portion including the line screen described above will beexplained. In the line screen test process in Step S3, the test patternprocess is performed with reference to an adjacent pixel of the pixel ofinterest as shown in FIG. 12. As input image signal explained in Step S3of the line screen test pattern process, any of the R, G, B imagesignals, such as a green signal(G), for example, may be used as well asluminance signals produced through the conversion of the R, G and Bsignals into a luminance signal Y, for example.

[0066] Referring to FIG. 11, a vertical line screen pattern test processperformed in Step S11 will be explained. In one example, it is assumedthat an image area 72 including a total of twenty-five pixels by fivepixels 71 with a pixel of interest at the center of the pixels 71. Thevertical line screen is an object to be observed in the example in thevertical line screen pattern test process in Step S11 and the verticalline screen referred to includes two or more lines which spread from onepoint to the other point along in the sub-scanning direction and thesesequentially varying lines with respect to thickness represent widthwiseimage gradation. The object of lines of interest includes an example ofthe vertical line screen consisting periodical cycle of one line withhigh density and two lines with low density. Each pixel value of thepixels 71 latitudinally along in the sub-scanning direction of the imagedata 64 (FIG. 9) is addition-processed in the process of an additionprocess 65. Therefore, unevenness of the image data density of pixels isdetermined sequentially in a line direction such as the main-scanningdirection by five pixels, for example. With the use of the additionvalues P1, P2, P3, P4 and PS, it is determined whether or not in eightpatterns of the subtraction/comparison processes 66 (FIG. 9) the imagedata of five pixels whose unevenness of image density has beendetermined match the object line screen pattern such as the one havingsequential cycle of the combination of one line with high density andtwo lines with low density, for example. For the purpose mentionedabove, the following calculation is performed. More specifically, in thecase of the combination of one thick line and two thin lines, anycombination patterns in terms of sequential lines include either thepattern of thin, thick, thin, thin and thick or the pattern of thin,thin, thick, thin and thick may be applied so that it is determined thatin the following step the addition values P1, P2, P3, P4 and P5 matcheither of the above-described two patterns. As shown in FIGS. 10C and10D, visible pixel values which are seen thick or thin lines radicallychange according to whether the figure portion adjacent to the pixel ofinterest C (FIG. 11) is a thick portion or a thin portion. Therefore,the density such as thick and thin, for example, is not an absolutevalue but is determined as a relative value determined in comparisonwith the adjacent pixels.

[0067] Referring back to FIG. 9, when the following conditions aresatisfied: P2−P1>th1, P2−P3>th1, P5−P3>th1 and P5−P4>th1 with th1referring to a threshold, the five pixels referred to so far aredetermined as a line screen and the information that the five pixels area line screen is output to the AND circuit 68 a with reference to 4subtraction/comparison processes 66. The value is input to an ANDcircuit and is processed in an AND test process 68 a. In this case, theaddition values P2 and P5 are determined, respectively, as relativelythick in density in comparison with adjacent addition values so that thefive pixels of the image data coincide with a pattern of combination ofthin, thick, thin, thin and thick patterns. Because the pixel ofinterest C is determined as including line screen and the signal outputis ON which indicates that the image data are a line screen.

[0068] Accordingly, when the following conditions are satisfied:P3−P1>th1, P3−P2>th1, P3−P4>th1 and P5−P4>th1, the five pixels aredetermined as a line screen and the information that the five pixels area line screen is output to the AND test process 68 b with reference tofour patterns of the subtraction/comparison processes 66 and the valueis input to the AND circuit 68 b and is processed in an AND test process68 b. In this case, the addition values P3 and P5 are determined,respectively, as relatively thick in density in comparison with adjacentaddition values so that the five pixels of the image data coincide witha combination pattern of thin, thin, thick, thin, and thick.

[0069] As shown in FIG. 9, to precisely determine a character portionwhere the pixel of the image data include lines in high density of FIG.10B from a line screen portion, determination that th2 of an inequalityP2−P3<th2 is a predetermined threshold and that the inequality P3−P2<th2is satisfied is performed with reference to a subtraction/comparisonunit 67 b, respectively. The respective test results produced from thelogical AND process described above are calculated in any of the ANDtest processes 68 a and 68 b, respectively. As described above, in thecase of electro-photography, because the bias of the density level inblack part of the character and the white background level is smallerthan the bias between the density level of a black portion of a figureand the background level, the subtraction/comparison process 67 adopts adetermination method that when there is too outstanding a bias between athick portion and a thin portion, an L level signal is output and animage is determined as not a line screen.

[0070] In the AND test process 68 a, the five pixels of the image datamatch the patterns of thin, thick, thin, thin, and thick by outputtingthe information to each of the AND circuits, respectively, obtaining anAND result from four patterns of the subtraction/comparison processes 66and one pattern of the subtraction/comparison process 67. When the biasbetween thick and thin patterns is not too great, the five pixels of theimage data processed in the AND process are determined as a line screen.Accordingly, in the AND test process 68 b, the pixel of the image datamatch the patterns of thin, thin, thick, thin and thick by outputtingthe information to each of the AND circuits and obtaining AND resultfrom four patterns of the subtraction/comparison processes 66 and onepattern of subtraction/comparison process 67. When the bias betweenthick and thin patterns is not too great, the five pixels of the imagedata are determined as a line screen.

[0071] In the OR test process 69, a test process to determine a pixel ofinterest C is a pixel that includes a line screen or not.

[0072] A horizontal line screen pattern test process in Step S12performs similar process to the vertical line screen pattern testprocess except for the direction of lines which spreads from one pointto the other point along in the sub-scanning direction in the verticalline screen test process replaced by the main-scanning direction whichspreads from one point to the other point along in the horizontal linescreen pattern test process. Specifically, the horizontal line screenpattern test process is identical with the vertical line screen patterntest process in that an image area 72 including five pixels.times.fivepixels 71 totaling at 25 pixels with the pixel of interest placed at thecenter of the 25 pixels. Components that are included in the horizontalline screen pattern test process are a plurality of the horizontal linescreens. The horizontal line screen referred to hereinafter includes aplurality of lines which spread from one point to the other point alongin the main-scanning direction and these sequentially varying line withrespect to thickness latitudinally represent image gradation. The objectline screen includes an example of a horizontal line screen includingone line with high density and two thin lines with low density.

[0073] In more detail, the horizontal line screen pattern test processperforms calculation similar to that of the addition process 65 of FIG.9, sequentially adding the five series of pixel values in a unit ofcolumn to the respective lines of image data. Thereby, the horizontalline screen pattern test process obtains addition values P1 through P5which indicates unevenness of the respective image data in thesub-scanning direction. Then, the horizontal line screen pattern testprocess sequentially delays the addition values P1 through P5 by everyone line as shown in the subtraction/comparison processes 66 and 67 ofFIG. 9. Thus, it may be determined whether the density of image data inthe sub-scanning direction matches either of a pattern thin, thick,thin, thin and thick or with a pattern thin, thin, thick, thin andthick. When a difference between thickness and thinness of image data istoo large in the sub-scanning direction, the image data may not bedetermined as a line screen. The processs identical to the AND testprocesses 68 a and 68 b of FIG. 9 and OR test process 69 of FIG. 9 areperformed, a determination to determine whether the horizontal linescreen is included is carried out.

[0074] An OR test process in Steps S13 allows a test result to beobtained by inputting an image data from one of the AND test circuits toan OR test circuit obtaining the processing result created from a testresult of the vertical line screen pattern test process. The results ofthe vertical line screen pattern test process using the AND circuits andthe horizontal line screen pattern test using the OR circuit enable atest result determining whether or not the vertical line screen or thehorizontal line screen exists to be provided.

[0075] As mentioned above, both the vertical line screen pattern testprocess in Step S11 and the horizontal line screen pattern test processin Step S12 include steps of detecting a line screen including one linewith high density and two lines with low density. Because when detectinga line screen with high density, it is a commonplace that a sequentialpattern of one thin line and two thick lines, an additionalsubtraction/comparison process 66 is required to be performed.

[0076] A comprehensive test process in Step S4 allows a test process todetermine whether or not each pixel 71 is a character portion or afigure portion with reference to each of the test result of the edgetest process in Step S1, the dotted image test process in Step S2 andthe line screen test process in Step S3. For example, when the imagedata are determined as containing an edge component in the edge testprocess in Step S1, determined as not containing a dot component in thedotted image test process in Step S2, and determined as not including aline screen in the line screen test process in Step S3, thecorresponding pixel is determined as a character portion, and when atleast one of the above-determinations is failed, the corresponding pixelis determined as a figure portion. The test signal thereof is output tothe image processing unit 7.

[0077] In the copying machine 1 according to the preferred embodiment ofthe present invention, a test signal representing either a characterportion or a figure portion output from the image-area separationapparatus 13 is output to the image processing unit 14. According to thetest result in the image area-separation apparatus 13, the informationcontents of the image processing performed in the image processingapparatus 14 are switched over.

[0078] More specifically, when the edge emphasis filter circuit 25receives a test signal which has determined that specified image dataare a character portion, the edge emphasis filter circuit 25 outputs asignal indicating that the edge emphasis filter circuit 25 has performedan edge gradation process for data of the pixel 71 of FIG. 11, forexample, which has been determined as a character portion. When the edgeemphasis filter circuit 25 receives a test signal which has determinedthat specified image data are a figure portion, the edge emphasis filtercircuit 25 outputs a signal indicating that the edge emphasis filtercircuit 25 has not performed an edge gradation process for data of thepixel 71 of FIG. 11, for example, which has been determined as a figureportion,

[0079] In accordance with the test result produced from the image-areaseparation apparatus 13, the information contents of an imagecompensation may change in the color compensation circuit 24 and anappropriate smoothing may be performed in the smoothing filter 22.

[0080] Therefore, with the above-described structure of the copyingmachine 1, the copying machine can carry out the image-separation toseparate character images from figure images by means of software whilethe SIMD-typed processor achieves a high-speed image data processing.

[0081] Next, the following embodiment is similar to the embodimentdescribed so far except for the information contents of a dotted imagetest process performed in the dotted image test process and a use of atable converter 81 as is explained later using together the SIMD-typedprocessor.

[0082] The contents of the process performed in Step S2 in the dottedimage test process is such that as shown in FIGS. 6 and 7 it isdetermined whether or not a pixel of interest is a dotted image withrespect to a bias of pixel value with the surrounding five pixels byfive pixels. In more detail, assuming the following conditions:

t 1=|f 22*2−(f 02+f 42)|, t 2=|f 22*2−(f 20+f 24)|, t 3=|f 22*2−(f 00+f44)|, and t 4=|f 22*2−(f 04+f 40)|.

[0083] and, the pixel of interest F22 is determined as a dotted imagewhen the following inequalities are satisfied:

th1>thrscreen, th2>thrscreen, th3>thrscreen and th4>thrscreen.

[0084] Therefore, the pixels determined as a dotted image are alignedsporadically in a form of dots. However, the dotted image including dotcomponents may not always be determined as dots because of an influenceby the status of printing of the read image data or by a noise problem.Hence, even though the image data are a dotted image, the image data aredetermined to be a character and the quality of the image aredeteriorated. It is not desired that a measure be taken such as anarrowing of the span of a threshold thrscreen, for example, as acounter-measure against the above-described misjudgment to incorrectlydetermine the dotted image as a character to worsen the print quality,and as a result, the character portion that is not a dotted image may bedetermined as dotted image.

[0085] When image data that are substantially a dotted image are notcorrectly determined as a dotted image, t1 through t4 as described aboveare proposed to be compensated on the premise that there are dottedimage surrounding the image data of interest, thereby making it morepossible to precisely judge a dotted image as a dotted image.

[0086] Thus, when the pixel of interest is determined as a dotted imageapplying the algorithm described so far, it is possible to determine apixel of a dotted image that is included in a dotted image as dottedimage in a precise fashion. Without excessively expanding the area ofthe dotted image to an area of a non-dotted image, the pixel which isincluded in the dotted image is precisely determined by applying adensity level of the dotted image in accordance with the pixel ofinterest to the surrounding pixels.

[0087] More specifically, as shown in FIG. 12, when calculation of thefollowing equations is performed when the weight coefficient w isdefined with respect to a distance in the main-scanning directionbetween a pixel of interest and a specified pixel determined as a dottedimage, a calculation is performed with the following equations.

t 1new=t 1*(1+w); t 2new=t 2*(1+w); t 3new=t 3*(1+w) and t 4new=t4*(1+w).

[0088] The pixel of interest can be determined as a dotted image whenthe above-described equations are finished and the values from t1 newthrough t4 new satisfy the following conditions, t1new=thrscreen;t2new=thrscreen; t3new=thrscreen and t4new=thrscreen.

[0089] In more detail, the following is an explanation referring toFIGS. 14A, 14B, 14C, 14D, 14E and 14F in which only t1 is referred to.However, the same applies to t2, t3 and t4. FIG. 14A defines pixels formpx1 through px5 and indicates that the pixels from px1 through px5 arepixels that are included in a dotted image. FIG. 14B shows a calculationresult of t1. FIG. 14C shows a result of the dotted image determinationby t1 wherein the threshold is 75. In this example, a pixel px1 isdetermined as a dotted image. However, a pixel px5 is not determined asa dotted image. Because the pixel px5 is included in the dotted image,the pixel px5 may probably be determined as a dotted image. However, thepixel px5 may not be determined as a dotted image because the thresholdof the pixel px5 is 48 and the value 48 is smaller than 75 which is thepredetermined threshold px5. FIG. 14D refers to a value of w. The valuew is determined accordingly with respect to a distance between the pixelpx1 which is determined as a dotted image and a specified pixel as shownin FIG. 14D. FIG. 14E shows a calculation result of t1 new. FIG. 14Fshows a dotted image determination result made by t1 new. FIG. 14F showsthat a dotted image determination result by t1 new. As a result of thedotted image determination by t1 new, the pixel p5 is determined as adotted image. In this way, a dotted image may be without fail detectedas a dotted image which has once not been detected as a dotted imagebecause of the noise problem, for example, by way of applying a degreeof the dotted image density.

[0090] Meanwhile, the SIMD-typed processor 41 is provided with a featureto execute uniform process simultaneously, for example, when a pluralityof instructions are given at the same time. In other words, a pluralityof the PEs 51 may be calculated simultaneously in parallel except for,as shown in FIG. 14A, 14B, 14C, 14D, 14E and 14F, a process withhysteresis which may cause process result in the past to influence thefollowing process in each of the processes. In the cases describedabove, the same process may not be executed simultaneously. Analternative is to sequentially perform each of the processes by everydata. Otherwise, it is impossible to effectively use the processperformed by the SIMD-typed processor 41.

[0091] For solving the above-described drawbacks, in the embodiment,sequential status transition processes are performed with the use of thehardware structure of the image-area separation apparatus 13 as will bedescribed below so that it is preferable to perform a sequential processwhich applies a degree of the dotted image density level described sofar in FIGS. 14A, 14B, 14C, 14D, 14E and 14F.

[0092] Referring now to FIGS. 15A and 15B, a block diagram shows ahardware structure of the SIMD-typed processor 41. In FIGS. 15A and 15B,the hardware structure of the SIMD-typed processor 41 has already beenexplained except for a function of the register file 43 which allows fora reading and writing of the image data into the specified register 51as well as a function provided with the register file 43 to enable anaccess from an external equipment through the SIMD-typed processor 41 tobe possible as well as a control by the global processor 42.

[0093] The image-area separation apparatus 13 is provided with a tableconverter 81 combined with the SIMD-typed processor 41, a memory andregister control circuit 84, a table (not shown) and an addressgenerating device 82.

[0094] The table converter 81 reads a specified register file 52 of theregister file 43 and writes data onto a specified register file 52 ofthe register file 43. The table converter 81 outputs to the addressgenerating device 82 the data read from the register 51 and writesoutput data from a table RAM 83 into the register 51. The memory andregister control circuit 84 inputs and outputs data with an externalequipment. The table RAM 83 which will be explained later is providedwith a function which performs conversion of tables. The addressgenerating device 82 converts the data read from the register 51 intoeach of the addresses for the table RAM 83.

[0095] Because a nonlinear process generally involves extremelycomplexed programming and an arithmetic process require changesaccording to respective operation data, the SIMD-typed processor 41applies a method for arithmetic calculation in which all the data afterprocessing are compared with the data before processing, provided as atable and the data after processing may be obtained. In more detail, avalue of the data before calculation to which a first address of a tableis added in the address generating device 82 is obtained as an addresspointer from the table RAM 83 and the data created from theabove-described process may be the data after calculation. Because thecalculation result data is fed back from the RAM 83 to the addressgenerating device 82, it is possible to realize the process withhisterisis which disseminates the process result to cause a previoustable conversion result to influence another table conversion resultthat follows with the use of the above-mentioned feedback function. Inthis case, the purpose is not a table state conversion but an intendedstate transition according to the input sequence. Hardware configurationof FIG. 15A and 15B allows the next state to be output from the inputdata and a preceding state which refers to the data after conversion.This conversion may be carried out by subtracting the table RAM 83. Inthe embodiment, the input data are a dotted image determination resultof 1 bit by t1 as shown in FIG. 14 C.

[0096] Referring to FIG. 16, the state is represented by 11 types ofstates of each having 4 bits in FIG. 16, which are categorized,according to a distance from the pixel, which is determined as a dottedimage by t1 of FIG. 14D.

[0097] The states shown in FIG. 16 are determined according to adistance from the pixel which is determined as a dotted image by a tracequantity of t1. When the distance from the pixel which is determined asa dotted image by t1 is ten or more pixels, the sate value is the samein FIG. 16.

[0098] Referring to FIG. 17, state transitions by input data or 1-bit ofthe dotted image determination result by t1 are determined in the way asshown in FIG. 17. The input data, for example, a dotted imagedetermination result of 1 bit which represents 1 when t1 is greater thanthrscreen and 0 when ti is equal to or smaller than thrscreen. In FIG.17, a state is shown inside the ellipse, a state transition is shown byan arrow and a number which is written above the arrows shows an inputvalue. The initial state when a sequential process starts is 0000. Theinformation content of the table in the table RAM 83 with bit width of32 bytes may be assigned according to each value in FIG. 18 and anynumber is assignable in the address 1011 or more because each of thecorresponding addresses is not used.

[0099] As described so far, even though the image-area separationapparatus 13 involves a sequential process as well as the image-areaseparation operation, the SIMD-typed processor 41 is capable ofcalculating an intermediate image data by way of a SIMD-typed processand capable of performing a sequential process of the intermediate databy the table converter 81. By so doing, an image data processing isaccelerated while software enabling the image-area separation processbetween a character portion and a figure portion to be realized.

[0100] This invention may be conveniently implemented using aconventional comprehensive purpose digital computer programmed accordingto the teachings of the present specification, as will be apparent tothose skilled in the computer art. Appropriate software coding canreadily be prepared by skilled programmers based on the teachings of thepresent disclosure, as will be apparent to those skilled in the softwareart. The present invention may also be implemented by the preparation ofapplication specific integrated circuits or by interconnecting anappropriate network of conventional component circuits, as will bereadily apparent to those skilled in the art.

[0101] Numerous additional modifications and variations are possible inlight of the above teachings. It is therefore to be understood thatwithin the scope of the appended claims, the disclosure of this patentspecification may be practiced otherwise than as specifically describedherein.

What is claimed is:
 1. An image-area separation apparatus, comprising: aSIMD processor performing a SIMD process for performing an image-areaseparation process; and, image-area separation means for performing animage-separation operation according to the SIMD process performed bythe SIMD processor.
 2. The image-area separation apparatus as defined inclaim 1, wherein the image-separation means is configured toimage-separate the image data into a character portion and a figureportion.
 3. The image-area separation apparatus as defined in claim 2,further comprising: a plurality of characteristic test means forperforming a plurality of characteristic tests to determine whether theimage data have specific characteristics; and, comprehensive test meansfor determining a comprehensive test result according to the pluralityof the characteristic tests means performed by the plurality of testmeans.
 4. The image-area separation apparatus as defined in claim 3,wherein said plurality of the characteristic means includescharacteristic test means configured to determine whether the image datainclude edge data.
 5. The image-area separation apparatus as defined inclaim 3, wherein said plurality of the characteristic means includescharacteristic test means configured to determine whether the image datainclude dotted image data.
 6. The image-area separation apparatus asdefined in claim 3, wherein said plurality of the characteristic meansincludes characteristic test means configured to determine whether theimage data include line screen image data.
 7. The image-area separationapparatus as defined in claim 3, wherein the plurality of characteristictest means include: edge test means for determining whether the imagedata include the edge data, and; dotted image test means for determiningwhether the image data include the dotted image data, wherein thecomprehensive test means determines that the image data include thecharacter portion when the edge test means determines the image datainclude at least one edge component and when the dotted image test meansdetermines that the image data include no dotted image component, anddetermines that the image data include the figure portion when at leastone of two events occurs in which the edge test means determines thatthe image data include no edge component and in which the dotted imagetest means determines that the image data include one of at least dottedcomponents.
 8. The image-area separation apparatus as defined in claim3, comprising: the edge test means for detecting whether the image datainclude the edge data; the dotted image test means for detecting whetherthe image data include the dotted image data; and a line screen testmeans for detecting whether the image data include line screen imagedata; wherein the comprehensive test means determines that the imagedata include the character portion when the edge test means determinesthe image data include at least one edge component; the dotted imagetest means determines that the image data include no dotted imagecomponent; and the line screen test means determines that the image datainclude no line screen; and wherein the comprehensive test meansdetermines that the image data include the figure portion when at leastone of the following three events occur: the edge test means determinesthat the image data include no edge component; the dotted image testmeans determines that the image data include one of at least dottedcomponents; and the line screen test means determines that the imagedata include at least one of line screen components.
 9. An image-areaseparation apparatus as defined in claim 1, further comprising: a dataconverter for converting data using the data as an address stored in aregister of a register file of said SIMD processor; a data tableconverter connected to the SIMD processor for converting data of a datatable using, as an address, data of a register provided to the SIMDprocessor; wherein said image-area separation apparatus performs theimage-area separation operation by causing the SIMD processor to performthe SIMD process and the data table converter to perform a sequentialoperation.
 10. The image-area separation apparatus as defined in claim9, wherein the image-area separation means is configured to requireintermediate data in the SIMD process and to perform the sequentialoperation for the intermediate data.
 11. An image-area separationapparatus which processes the read image of the original image data,comprising: a SIMD processor performing a SIMD process for performing animage-area separation process; and image-area separation means forperforming an image-separation operation according to the SIMD processperformed by the SIMD processor.
 12. An image forming apparatus,comprising: an image reading apparatus to read an image of an originalimage data; an image-area separation apparatus which processes the readimage of the original image data, said image-area separation apparatus,comprising: a SIMD processor performing a SIMD process for performing animage-area separation process; and image-area separation means forperforming an image-separation operation according to the SIMD processperformed by the SIMD processor; an image-processing means for switchingover contents of the image data in accordance with the result of theimage-separation operation performed by the image-separation apparatus;and image forming means for forming an image onto a recording sheet inaccordance with the image data read by the image reading apparatus. 13.A computer-readable program for an image-area separation embodied on aninformation storage medium, said computer-readable program, comprisingprocessing routines executed by a SIMD processor, comprising the stepof: causing the SIMD processor to perform the image-area separation forimage-separating the image data.
 14. The computer-readable program forthe image area separation as defined in claim 13, wherein the image-areaseparation operation comprises separating the image data into acharacter portion and a figure portion.
 15. The computer-readableprogram for the image area separation as defined in claim 14,comprising: a processing routine to cause said processor to execute aplurality of characteristic test means for performing a plurality ofcharacteristic tests to determine whether the image data have specificcharacteristics; and a comprehensive test means for determining acomprehensive test result according to the plurality of thecharacteristic tests means performed by the plurality of test means. 16.The computer-readable program as defined in claim 15, wherein one of aplurality of the characteristic test processes is an edge test processconfigured to determine that the image data include an edge component.17. The computer-readable program as defined in claim 15, wherein one ofa plurality of the characteristic test processes is a dot image testprocess configured to determine that the image data include a dottedimage component.
 18. The computer-readable program as defined in claim15, wherein one of a plurality of the characteristic test processes is aline screen test process configured to determine that the image datainclude a line screen components of the image data.
 19. Thecomputer-readable program as defined in claim 13, wherein the image-areaseparation process causes the SIMD-typed processor to execute said SIMDprocess and to perform the image-area separation by allowing a tableconverter which performs a table conversion in which register data ofthe register file of the SIMD-typed processor are an address to executea sequential process.
 20. The computer-readable program as defined inclaim 19, wherein the image-area separation is configured to calculateintermediate data and to perform the sequential process in accordancewith the intermediate data.
 21. A computer-readable medium having storedthereon computer-executable instructions which include the image-areaseparation, comprising: said computer-readable program, comprisingprocessing routines executed by a SIMD processor, comprising the stepof: causing the SIMD processor to perform the image-area separation forimage-separating the image data.
 22. The computer-readable medium asdefined in claim 21, wherein the image-area separation operationimage-separates the image data into a character portion and a figureportion.
 23. The computer-readable medium as defined in claim 22,comprising: a plurality of characteristic test means for performing aplurality of characteristic tests to determine whether the image datahave specific characteristics; and, comprehensive test means fordetermining a comprehensive test result according to the plurality ofthe characteristic tests means performed by the plurality of test means.24. The computer-readable medium as defined in claim 23, wherein one ofa plurality of the characteristic test processes is an edge test processconfigured to determine that the image data include an edge component.25. The computer-readable medium as defined in claim 23, wherein one ofa plurality of the characteristic test processes is a dot image testprocess configured to determine that the image data include a dottedimage component.
 26. The computer-readable medium as defined in claim23, wherein one of a plurality of the characteristic test processes is aline screen test process configured to determine that the image datainclude a line screen components of the image data.
 27. Thecomputer-readable medium as defined in claim 13, wherein the image-areaseparation process causes the SIMD-typed processor to execute said SIMDprocess and to perform the image-area separation by allowing a tableconverter which performs a table conversion in which register data ofthe register file of the SIMD-typed processor are an address to executea sequential process.
 28. The computer-readable medium as defined in ofclaim 19, wherein the image-area separation is configured to calculateintermediate data and to perform the sequential process in accordancewith the intermediate data.